Emys wyomingensis, Leidy.
Cont. to Ex. Vert. Fauna, p. 140.
Represented by six perfect shells from Cottonwood and Dry Creeks, and
Henry's Fork, and a shoulder girdle from Cottonwood Creek, which is
provisionally referred to this species.
This species, when adult, was upward of a foot in length, and in
the composition of the shell, number of scutes, etc., resembled the
living species of the genus.
_The Shoulder Girdle_ has the form characteristic of the _Emydidæ_,
but presents some peculiarities. The scapula is short, not being
as long as the coracoid, and is not so straight or cylindrical as
is usual in _Emys_; but is compressed, and somewhat recurved, and
tapers towards the upper extremity, which is marked by a smooth
rounded facet for the cartilaginous supra-scapula. The precoracoid
is long, sub-cylindrical at its origin, but becomes broad and flat
distally; at the extremity it is longitudinally striated. The
proximal end is flexed forward at an obtuse angle, and is expanded to
form the long suture with the scapula and coracoid. It contributes
considerably to the glenoid cavity. The coracoid is remarkably long,
and after leaving the sutures with the other elements of the girdle,
becomes very broad and thin. This is most marked distally. The
anterior border is thickened, and the bone is slightly concave on
both surfaces.
The three parts of the shoulder girdle are united by distinct bony
symphyses; they differ from some of the modern species, in which
there is only a ligamentous union between the coracoid and the other
parts. It presents a further difference in the long and slender neck
which is formed by the flexing of the precoracoid, and in the shallow
and subcircular glenoid cavity. The short scapula and long coracoid
would indicate a species with a low, broad carapace, as was probably
the case in _E. wyomingensis_, though much difficulty has been
experienced in determining this point, owing to the distortion of the
specimens.
_Measurements._
M.
Length of neck to point between coracoid and precoracoid ·0345
Length of coracoid (about) ·133
Length of precoracoid ·114
Length of scapula (about) ·126
BAENA, Leidy.
Baena undata, Leidy.
Cont. to Ex. Vert. Fauna, p. 160.
Three nearly perfect shells of different ages, from Dry and
Cottonwood Creeks.
TRIONYX, Geoffr.
Trionyx uintaensis, Leidy.
Cont. to Ex. Vert. Fauna, p 176.
Cottonwood Creek.